L.B. White Therma Grow HW120 Manuel Du Propriétaire page 8

8
Therma Grow™ Greenhouse Heaters
7. Check for gas leaks and proper function upon
heater installation, when relocating, and after
servicing. Refer to leak check instructions within
installation section of this manual.
8. This heater should be inspected for proper opera-
tion by a qualified service person before each use
and at least annually.
9. Always turn off the gas supply to the heater if the
heater is not going to be used.
10. Heaters requiring 230 volts electrical supply must
have electrical wiring consisting of two hot leads,
a neutral lead, and a ground lead. All Therma
Grow heaters, regardless of voltage, must be
properly connected to a grounded electrical sup-
ply. Failure to use a grounded electrical supply
can result in electrical shock, serious injury, or
death.
11. Direct ignition heaters will make up to three trials
for ignition. If ignition is not achieved, the control
system will lock out the gas control valve. If gas
is smelled after system lock out has occurred,
immediately close all fuel supply valves. Do not
relight until you are sure that all gas that may
have accumulated has cleared away. In any
event, do not relight for at least 5 minutes.
12. I n a hanging type installation, rigid pipe or copper
tubing coupled directly to the heater may cause
gas leaks during movement, and therefore must
not be used. Use only gas hose assemblies that
are reated and approved for L.P. Gas and natural
gas in a hanging type of installation.
13. Installations not using the gas hose supplied with
this heater must connect dimensionally using
American National Standard Wrought Steel and
Wrought Iron Pipe B36/10-1970. (Aluminum
piping or tubing shall not be used.) Copper tubing
when used for conveying natural gas, shall be
internally tinned or equivalently treated to resist
sulphur.
Owner's Manual • Therma Grow™
Installation Instructions
General
Direct fired heaters discharge combustion by-products
with the heated air in to the area being heated. These
include CO, CO2, NO, NO2, and Ethylene. These gases
can result in harm to the worker or the plants.
This greenhouse heater has been specifically developed
for very low levels of these combustion by-products.
However, it is necessary to have an exchange of air
within the greenhouse to avoid accumulation of these
gases to a harmful level over an extended period of
operating time.
Greenhouses have a natural air leakage factor. This
natural leakage is influenced by the design and physical
condition of the greenhouse as well as wind conditions
and other factors. This natural leakage factor can not be
relied upon as being sufficient to provide the necessary
air exchange within the greenhouse. Proper installation
of this heater must include provision for adequate air
exchange as follows:
Indoor Mounted Heater:
Therma Grow 120 Models
-- An exhaust fan capable of providing at least 300 cfm of
discharge air.
-- An inlet shuttered louver of at least 120 sq. in. area.
Therma Grow 220 Models
-- An exhaust fan capable of providing at least 550 cfm of
discharge air.
-- A shuttered inlet of at least 120 sq. in. area.
Regardless of heater model:
-- The inlet shutters must be electromechanically oper-
ated and electrically interlocked with the heater such
that the heater can not operate if the inlet shutters do
not open when heating is required.
-- Refer to Indoor Ventilation Requirements in this
manual.
Outdoor Mounted Heater:
Therma Grow 120 Models
-- An exhaust shuttered louver of at least 120 sq. in. area.
Therma Grow 220 Models
-- An exhaust shuttered louver of at least 220 sq. in. area.